A detailed study on YBa2 Cu 3O7 (YBCO) films with BaZrO 3 (BZO) inclusions (YBCO-BZO) deposited on SrTiO 3 substrate with different BZO contents is presented. X ray diffraction, SEM imaging and superconductive critical temperature (Tc) measurements were performed to evaluate film growth quality. Independently from the BZO content, all YBCO-BZO films showed values close to that of pure YBCO indicating that the reduction which is usually observed on YBCO-BZO films can be successfully recovered by changing the deposition conditions. All YBCO-BZO films showed an improved critical current density (Jc) dependence on magnetic field if compared to the typical Jc(H) of YBCO, resulting in higher irreversibility fields up to 9 T at 77 K. SEM observation on etched samples suggests a direct link between the defect density measured in YBCO-BZO samples and that calculated from the observed in field performances. The analysis of Jc(B) as a function of applied magnetic field direction revealed that the pinning due to isotropic pinning centers typical for YBCO is coupled with a c-axis correlated pinning in YBCO-BZO which can be ascribed to BZO induced columnar defects. Jc(B) recorded at several temperatures down to 10 K revealed matching effect features.
A., A., V., G., G., C., A. A., A., A., M., A., R., et al. (2009). Transport property improvement by means of BZO inclusions in PLD grown YBCO thin films. IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, 19, 3399-3402 [10.1109/TASC.2009.2019253].